461 results about "Adaptive loop filtering" patented technology

A mechanism for processing video data is disclosed. One or more extended taps are determined for use in an adaptive loop filter (ALF). A conversion is performed between a visual media data and a bitstream based on the extended tap in the ALF. The extended tap may receive input data from different pictures than the current picture and / or from outside the spatial domain.

An example method of video processing includes: determining, for a conversion between a chroma block of a current processing unit of a current subpicture of a current picture of a video and a bitstream of the video, that a cross component adaptive loop filtering operation is applied to the chroma block, wherein the current picture comprises one or more subpictures; and performing the conversion based on the determining, wherein in the cross component adaptive loop filtering operation, a chroma sample of the chroma block is filtered based on information of luma samples, and wherein one or more luma samples located outside the current processing unit are excluded from the filtering of the chroma sample.

A mechanism for processing video data is disclosed. A filter is applied to a video unit. The filter employs an extended tap for a first sample in the video unit and a spatial tap for a second sample in the video unit. A conversion is performed between a visual media data and a bitstream based on the video unit.

A method and apparatus for video decoding / encoding are provided. In the provided method, a decoder obtains at least one secondary signal by applying at least one fixed filter to a primary signal. The at least one fixed filter is trained offline. The decoder obtains one or more spatially adjacent samples associated with the current sample. One or more spatially adjacent sample points are from at least one of the primary signal or the at least one secondary signal. The decoder obtains filtered sample points by applying at least one online filter to one or more spatially adjacent sample points associated with the current sample point.

A method of video processing includes determining, for a conversion between a current block of a video and a bitstream representation of the video using a coding tool that accesses samples outside of the current block, that neighboring samples used for the conversion are unavailable. Samples that are located across a boundary of a video unit of the video are considered as unavailable samples. The method also includes performing, based on the determining, the conversion by padding samples in place of the neighboring samples that are unavailable. The padding samples are determined using samples that are restricted to be within a current processing unit associated with the current block.

A method of video processing includes making a determination for a conversion between a video region of a video and a bitstream representation of the video to use a cross-component adaptive loop filtering (CC-ALF) tool for refining chroma samples values using luma sample values; and performing the conversion based on the determination, wherein the refining includes correcting the chroma sample values using a final refinement that is a further refinement of a first refinement value determined by selectively filtering the luma sample values.

A video coder may receive video data, and apply a filter to a plurality of categories of samples of the video data. The plurality of categories of samples may include two or more of an input of a fixed filter, an output of the fixed filter, an input of a signaled filter, an output of the signaled filter, an input of an adaptive loop filter, an output of the adaptive loop filter, an input of a sample adaptive offset (SAO) filter, an output of the SAO filter, an input of a bilateral filter, an output of the bilateral filter, an input of a cross component SAO filter, an output of the cross component SAO filter, an input of a deblocking filter, an output of the deblocking filter, filtered reconstructed residual data, dequantized coefficients, filtered dequantized coefficients, a predictor, or a filtered predictor.

An encoder includes circuitry and memory coupled to the circuitry. The circuitry, in operation, generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component, and generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component. The circuitry modifies the first coefficient value by performing an arithmetic right shift by 7 bits on the first coefficient value. The circuitry generates a third coefficient value by adding the modified first coefficient value to the second coefficient value, and encodes a third reconstructed image sample of the chroma component using the third coefficient value.

A device for decoding video data determines a pre-filtered reconstructed block of video data; applies one or more of a deblocking filter or a sample adaptive offset filter to the pre-filtered reconstructed block to determine a filtered reconstructed block; applies an adaptive loop filter (ALF) to the filtered reconstructed block to determine a final filtered reconstructed block, wherein to apply the ALF to the filtered reconstructed block, the device is further configured to determine a difference value based on a difference between a value of a current sample of the filtered reconstructed block and a value of a pre-filtered neighboring sample; apply a filter to the difference value to determine a sample modification value; and determine a final filtered sample value based on the sample modification value.

A mechanism for processing video data is disclosed. The mechanism includes determining to apply an adaptive loop filter (ALF) to a first component of a video unit. The ALF includes one or more extended taps. The one or more extended taps utilize an input source other than spatial neighbor samples of the first component. A conversion is performed between a visual media data and a bitstream based on the ALF.

Methods, apparatus, systems, and articles of manufacture are disclosed to improve video encoding. An example apparatus includes at least one memory, instructions, and processor circuitry to generate a pool of clipping index set candidates by executing a machine learning model, select a clipping index set from the pool of the clipping index set candidates based on a rate distortion cost associated with the clipping index set, the clipping index set including clipping coefficients, and filter a video frame based on the clipping coefficients.

A method for adaptive loop filtering is provided that includes determining a coefficient value for each coefficient position of an adaptive loop filter, applying the adaptive loop filter to at least a portion of a reconstructed picture using the coefficient values, and entropy encoding coefficient values into a compressed bit stream using predetermined short binary codes, wherein the short binary code used depends on the coefficient position of the coefficient value.

A mechanism for processing video data is disclosed. The mechanism includes determining to apply an adaptive looper filter (ALF) with an extended tap to a picture in a video. An intermediate filtering result of a second filter is used as input for the extended tap. A conversion is performed between a visual media data and a bitstream based on the ALF.

Provided are a video encoding method, a video decoding method, and a bitstream generating method using an identifier indicating whether a corresponding chroma component is filtered by an adaptive loop filter (ALF).SOLUTION: The video encoding method includes encoding an image to generate a bitstream. In the bitstream, a first syntax element is configured to indicate whether the first chromaticity component is filtered with an adaptive loop filter (ALF), and a second syntax element is configured to indicate whether the second chromaticity component is filtered with the ALF.SELECTED DRAWING: Figure 5

The embodiment of the invention provides a video coding method, device and equipment based on adaptive loop filtering. According to the technical scheme provided by the embodiment of the invention, by determining the transform residual absolute value and information and / or motion vector information of the plurality of image blocks in the to-be-coded image frame, when the time domain layering level of the to-be-coded image frame is greater than the preset level, the to-be-coded image frame is coded; and determining whether the to-be-coded image frame is a still image frame or not according to the transform residual absolute value sum information and / or the motion vector information, and when the to-be-coded image frame is the still image frame, performing coding processing without adaptive loop filtering on the to-be-coded image frame, skipping partial adaptive loop filtering processing with poor effect, and performing coding processing without adaptive loop filtering on the to-be-coded image frame. Computing resources consumed by self-adaptive loop filtering processing are reduced, and the video coding efficiency is effectively improved.

Systems, methods, and instrumentalities are disclosed herein for determining whether to apply a filter and / or the parameters of a filter to be applied to a video block based on depth and / or motion information associated with the video block. The determination may be made based on the existence or non-existence of a depth discontinuity in the video block. The filter may be a bilateral filter, a deblocking filter, a sample adaptive offset (SAO) filter, a cross-component sample adaptive offset (CC-SAO) filter, or an adaptive loop filter.

A mechanism for processing video data is disclosed. The mechanism includes determining to apply an extended tap in an adaptive loop filter (ALF). The ALF may also include a spatial tap, and the extended tap may be different from the spatial tap. A conversion is performed between a visual media data and a bitstream based on the ALF.

An encoder includes circuitry and memory coupled to the circuitry. The circuitry, in operation, generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component, generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component, and clips the second coefficient value. The circuitry generates a third coefficient value by adding the first coefficient value to the clipped second coefficient value, and clips the third coefficient value. The circuitry encodes a third reconstructed image sample of the chroma component using the clipped third coefficient value.

A mechanism for processing video data is disclosed. The mechanism includes using, during a conversion between a video and a bitstream of the video, side information as input to an adaptive loop filter (ALF). A conversion is performed based on the ALF.

A method of video processing includes determining, for a conversion of a block of a video picture in a video and a bitstream representation of the video, gradients of a subset of samples in a region for a classification operation in a filtering process. The region has a dimension of M×N and the block has a dimension of K×L, M, N, K, L being positive integers. The block is located within the region. The method also includes performing the conversion based on the determining.

A device for decoding encoded video data is configured to determine a block from the encoded video data; determine a bit depth for an adaptive loop filter from a plurality of available bit depths for the adaptive loop filter; determine coefficient values for a set of filter coefficients for the adaptive loop filter based on the bit depth; apply the adaptive loop filter to the block to determine a filtered block of video data; determine a decoded version of the block of video data based on the filtered block of video data; and output a decoded picture of video data that includes the decoded version of the block of video data.

A method and an apparatus are disclosed for video coding CC-ALF based on a nonlinear cross-component relation. A video decoding device obtains a reconstructed frame that is an output of a sample adaptive offset (SAO) filter and generates an adaptive loop filter output (ALF output) by inputting the reconstructed frame into an adaptive loop filter (ALF). The ALF output includes a luma ALF output and a chroma ALF output. The video decoding device generates corrected values of a chroma component by inputting the luma ALF output into a nonlinear cross-component ALF (nonlinear CC-ALF) and generates an enhanced chroma ALF output by summing the corrected values of the chroma component and the chroma ALF output.

A video encoder and video decoder are configured to determine a filter from a first temporal layer having a first temporal layer ID, determine a scaling factor for the filter from a second temporal layer having a second temporal layer ID, and store the scaling factor in a buffer for future usage based on the second temporal layer ID being less than or equal to the first temporal layer ID.

According to the disclosure of the present document, an image decoding method performed by a decoding device comprises the steps of: acquiring, through a bitstream, image information including prediction mode information and residual information; deriving a prediction mode of a current block on the basis of the prediction mode information; deriving prediction samples on the basis of the prediction mode; deriving residual samples on the basis of the residual information; generating reconstruction samples on the basis of the prediction samples and the residual samples; deriving filter coefficients for an adaptive loop filter (ALF) procedure for the reconstruction samples; and generating modified reconstruction samples on the basis of the reconstruction samples and the filter coefficients, wherein the image information includes a first adaptation parameter set (APS) including an ALF data field, and the ALF data field includes ALF parameters used to derive the filter coefficients.

Example methods, devices, and computer-readable media are described. An example device for coding video data includes one or more memories configured to store the video data. The device includes one or more processors operably coupled to the one or more memories. The one or more processors are configured to reconstruct a current block of the video data. The one or more processors are configured to apply a cross component adaptive loop filter (CCALF) to an input to generate a filtered pixel. The input includes one or more chroma samples of a current pixel of the current block. The one or more processors are configured to generate a filtered block based on the current block, the filtered block including the filtered pixel.

An exemplary method for video processing includes: determining whether to enable a cross-component adaptive loop filtering tool for a current video block of a video based on the color properties of the video for the conversion between the current video block of the video and the bitstream representation of the video. The method further includes performing the conversion according to the determination.

A mechanism for processing video data is disclosed. The mechanism includes determining to use at least one extended tap in an adaptive loop filter (ALF). A conversion can then be performed between a visual media data and a bitstream based on the ALF. The ALF may also employ a conditional filter shape switch.

A method of filtering reconstructed video data is disclosed. The method comprising: inputting reconstructed luma component sample values; deriving a filtered sample value by using cross component filter coefficients and the reconstructed luma component sample values prior to an adaptive loop filtering process; deriving a refinement value for chroma components by using the filtered sample value; and deriving a refined chroma sample value by using a sum of a sample value of chroma components and the refinement value for chroma components.